DAYTONA BEACH, Fla. - There are two certainties heading into the Daytona 500: Kevin Harvick is the favorite, and no one is sure what the action will look like in the Great American Race.

Harvick remained perfect through Speedweeks on Thursday by winning the first of two 150-mile Budweiser Duel qualifying races, and the victory has positioned him as the top pick to win NASCAR's version of the Super Bowl.

Being labeled the favorite is the last thing the 2007 Daytona 500 winner wanted headed into Sunday's season opener.

"We like to be the lame-duck underdog. That's what we're shooting for," Harvick said.

"We've been fortunate to win the first two races of Speedweeks," Harvick said. "We've just got to keep a level head on our shoulders, not get too high over what we've done, just do the same things that we've done.

"If it's meant to be, it's meant to be. I think we definitely have the car and team to be in contention to do that."

But nobody is quite sure what the 500 will look like with NASCAR's new Gen-6 race car. Sunday's race will go off with a full 43-car field, double the number of cars that ran in Thursday's qualifying races. There were 19 cars in Saturday's exhibition.

Kyle Busch, winner of the second duel, believes more cars on the track will create a different race than what fans have seen.

"With more cars out there, we might see it be a little bit different come Sunday," Busch said. "There were half the field in each race, obviously.

"There's going to be twice as many good cars, twice as many middle-of-the-pack cars, twice as many back-of-the-pack cars. If you can get your car handling, driving, feeling good, you'll be able to be one of the guys that's up front."

Busch gave Toyota its first victory of Speedweeks and snapped Chevrolet's dominance. Harvick took the new Chevrolet SS to Victory Lane twice, and Danica Patrick put it on the Daytona 500 pole in time trials.

The starting field for the Daytona 500 is set by the results from the pair of 60-lap qualifiers, but Patrick held on to the pole by running a safe race in the first qualifier. She started first in the first qualifier, raced a bit early and then faded back to run a conservative race and ensure she will start first in the 500.